Pulsus Paradoxus

Definition

  • Pulsus Paradoxus: decreased systolic blood pressure with inspiration
    • Observed in Arterial Line Waveform (see Arterial Line, [[Arterial Line]])

Etiology

Cardiac

  • Cardiogenic Shock (see Cardiogenic Shock, [[Cardiogenic Shock]])
  • Constrictive Pericarditis (see Constrictive Pericarditis, [[Constrictive Pericarditis]])
    • Epidemiology: pulsus paradoxus is less common in constrictive pericarditis
  • Hypovolemia (see Hypovolemic Shock, [[Hypovolemic Shock]])
    • Epidemiology: in sepsis
    • Respiratory Pulse Pressure Variation, Delta PP ((Max-Min Pulse Pressure)/Average Pulse Pressure), Predicts Cardiac Output Response to an Intravenous Fluid Challenge Better than CVP and PCWP (Am J Resp Crit Care Med, 2000) [MEDLINE]
  • Tamponade/Pericardial Effusion (see Tamponade, [[Tamponade]] and Pericardial Effusion, [[Pericardial Effusion]])
    • Epidemiology: pulsus paradoxus is commonly observed in the setting of tamponade
    • Physiology: pulsus paradoxus is observed during spontaneous breathing
    • Diagnosis
      • Echocardiogram
        • Diastolic RV and LV Collapse
        • Systolic RA and LA Collapse
        • Increased Variability in Mitral (>25%) Inflow Velocity
        • Increased Variability in Tricuspid (>40%) Inflow Velocity

Pulmonary

  • Acute Pulmonary Embolism (PE) (see Acute Pulmonary Embolism, [[Acute Pulmonary Embolism]])
    • Physiology: RV outflow obstruction
  • Asthma (see Asthma, [[Asthma]])
    • Epidemiology: pulsus paradoxus is common in asthma
    • Physiology:
  • Chronic Obstructive Pulmonary Disease (COPD) (see Chronic Obstructive Pulmonary Disease, [[Chronic Obstructive Pulmonary Disease]])
    • Physiology:
  • Tension Pneumothorax (see Pneumothorax, [[Pneumothorax]])

Other

  • Abdominal Compartment Syndrome (see Abdominal Compartment Syndrome, [[Abdominal Compartment Syndrome]])
    • Physiology: due to transmission of high intra-abdominal pressures to thorax -> impaired right-sided venous return
  • Anaphylaxis (see Anaphylaxis, [[Anaphylaxis]])
  • Superior Vena Cava (SVC) Syndrome (see Superior Vena Cava Syndrome, [[Superior Vena Cava Syndrome]])
    • Physiology: RV inflow obstruction

References

  • Relation between respiratory changes in arterial pulse pressure and fluid responsiveness in septic patients with acute circulatory failure. Am J Respir Crit Care Med. 2000 Jul;162(1):134-8 [MEDLINE]
  • Focused critical care echocardiography. Crit Care Med. 2013;41:2618–2626 [MEDLINE]
  • Advanced echocardiography for the critical care physician: Part 1. Chest. 2014;145:129–134 [MEDLINE]
  • Advanced echocardiography for the critical care physician: Part 2. Chest. 2014;145:135–142 [MEDLINE]